Dehumidifying Fans reduce the amount of moisture in a shower / bath / wet room setting. These fans turn on automatically when the ceiling dew point reaches a pre-determined level. These fans stay on until the room is dry. If you are used to a morning shower, turning on your bathroom fan to reduce the moisture, and then before you leave for work you turn off the fan, the amount of moisture may not be reduced thoroughly. With the automatic dehumidfying fans they will use their internal sensors to make that call on when to turn off. These fans also come with a manual on/off switch. We love these in the master bath units as a time saver, moisture reducer and as an efficient system. Would you like one of these ceiling fans in your bathroom suite?